Cellulose-ether solvent and composition



Patented Nov. 7, 1922.-

NITED STATES" PATENT OFFICE.

fi'lllEWAR'I' J. CARROLL, OF ROCHESTER, NEW YORK, ASSIGNOR TO EASTMAN KODAK COMPANY, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

OELLULOSE-ETHER SOLVENT AND COMPOSITION.

Ito Drawing.

To all whom it may c0'rwem:

Be it known that I, STEWART J. CARROLL, a citizen of the United States of America, residing at Rochester, in the county of Monroe and- State of New York, have invented certain new and useful Improvements in Cellulose-Ether Solvents and Compositions, of which the following is a full, clear, and exact specification.

This invention relates to solvents for making strong solutions of cellulose ether and also relates to the cellulose ether compositions produced by the aid of such solvents. One object of my invention is to provide a solvent which Wlll dissolve such large proportions offcellulose ethers that thick or viscous flowable solutions may be obtained for use in plastic and film making arts; Another object of my invention is to provide a cellulose ether solution which may be manufactured into strong, flexible, transparent film on the machines and by the methods now in use.

In U. S. Patent No. 1,188,376, Lilienfeld,

June 20, 1916, there are disclosed a series of alkyl ethers of cellulose. Certain of these are practically insoluble in water, and my invention relates, but is not limited, to the ethers having that property. While the ethers form thin solutions in the lower monohydroxy aliphatic alcohols or phenol, it has been found that such single solvents by themselves do not dissolve a sufiicient proportion of the ethers to make a desirably thick fiowable composition or dope, such as may be used in the manufacture of photographic film base by customary meth ods, or in the other plastic arts.

I have discovered that an adequately strong and useful solvent may be prepared by mixing phenol with one or more of the lower monohydroxy aliphatic alcohols. For example, I may use from 90 to parts of phenol and 10 to 50 parts by weight of the alcohol, say methyl or ethyl alcohol as an illustration. In the preferred form of my invention, I use equal parts by weight of phenol and meth 1 alcohol. While the amountof ether that may be dissolved in such mixed solvents may be varied as desired over a large range, it is noted; IQ! the Application filed May 24, 1921. Serial No. 472,268.

,cous flowable solution.

Other substances which impart additional suppleness, or incombustibility, or other qualities, to the film may also beadded to the dope, such, for instance, as triphenyl or tricresyl phosphate, camphor, etc. In the formation of the film a considerable amount of phenol is left therein, due to its relatively. low volatility. It imparts useful properties to such film.

The ingredients are of the ordinary commercial type and sufficiently purified for the process of film manufacture, so as to give a dope yielding films having the proper relative freedom from color. This viscous-flowable dope above described can be used in connection with the usual film-forming apparatus without the necessity of expensive alterations in the latter. By the term lower monohydroxy aliphatic alcohols, I include such alcohols having less than 6 carbon atoms.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is by weight of phenol and 10 to 50 parts of alower monohydroxy aliphatic alcohol.

5. A composition of matter, comprising water-insoluble ethyl cellulose, phenol and methyl alcohol.

Signed at Rochester, New York, this 14th day of May, 1921.

STEWART J CARROLL,

2 Certificate of Correction.

It is hereby certified that in Letters Patent No. 1,434,426, granted November 7,

1922, upon the application of Stewart J. Carroll, of Rochester, New York, for

an improvement in Cellulose-Ether Solvents and Compositions, an error appears in the printed specification requiring correction as follows: Pege'l, line 48, afterthe word methyl insert the words or ethyl; and that the said Letters Patent should he read with this correction therein that the same may conform to the record of the case in the Patent Office. I

Signed and. sealed this 12th day of December, A. D., 1922.

[SEAL] KARL FENNING,

Acting Commissioner of Patents. 

